Excavator Lift Capacity Calculator
Check an excavator lift against the manufacturer's rated lift capacity chart, with the quick hitch and lifting accessories counted in, the way a lift plan does it. Built by a CPCS A61 Appointed Person who writes and reviews excavator lift plans.
Excavator lift calculator
Chains or slings, master link, shackles, any spreader beam
From the hitch plate or the maker's data. Bucket off.
At the lift point radius and height, for this machine's set-up
RMT plans to 90% unless the site sets a lower limit
Before the lift
- Bucket removed: lift from the quick hitch lifting eye or another rated lifting point
- The rated lift capacity chart in the cab is for this boom, arm, counterweight and undercarriage
- Capacity read at the real radius and lift point height, over the side if the load slews round
- Overload warning device switched on, and boom lowering control (hose burst) valves fitted
- Quick hitch locked, its safety pin in, and within its thorough examination
- Firm, level ground, and the operator and slinger trained for excavator lifting
A preliminary check, not a lift plan. The ground, the exclusion zone, overhead services and the rigging all need planning too. Need an excavator lift plan?
How the calculation works
1. Read the capacity from the maker's chart
Find the column for the radius from the slew centre to the load and the row for the height of the lift point, on the chart for the boom and arm fitted, the counterweight, the undercarriage and blade position, over the front or over the side. Under ISO 10567 that figure is already the smaller of 75% of the tipping load and 87% of the hydraulic lift capacity. A blank cell means no lifting at that point.
2. Work out the gross load
Gross load = load + lifting accessories + quick hitch
The charts generally exclude the bucket and the hitch, and the CPA guidance says the hitch has to be added to the load. RMT plans every lift with the bucket off; if any bucket or attachment stays on, its weight goes in too.
3. Check the utilisation
Utilisation = gross load ÷ chart capacity × 100%
RMT plans excavator lifts to no more than 90% unless the site sets a lower limit; railway and some client sites do. Over 100% the lift must not be made with that machine at that radius.
Worked example
An excavator lowers a 1,760 kg concrete chamber ring into a manhole box at 6.0 m radius, on a 3-leg chain weighing 45 kg from a 260 kg quick hitch, bucket off. The maker's chart gives 4,850 kg at that radius and height.
- Gross load: 1,760 + 45 + 260 = 2,065 kg
- Utilisation: 2,065 ÷ 4,850 = 42.6%, within 90%
- Heaviest load within 90%: 4,850 × 0.9 − 305 = 4,060 kg
Illustrative figures only. Use the weights and the chart for your own machine.
Questions
How is an excavator’s lift capacity worked out?
Manufacturers rate excavators to ISO 10567. The figure in each cell of the lift capacity chart is the smaller of 75% of the load that would tip the machine and 87% of what the hydraulics can lift at that radius and height. Figures marked with an asterisk are limited by the hydraulics rather than stability.
Do I add the quick hitch to the load?
Yes. The CPA guidance on lifting with excavators says the quick hitch, and any bucket or accessory left on, has to be added to the load when checking it against the rated capacity, and the makers’ chart notes say the same for slings and lifting devices. Charts generally exclude the bucket and hitch, so they come off the capacity or, the same thing, go on the load.
Can I lift with the bucket on?
RMT plans every excavator lift with the bucket removed, lifting from the quick hitch lifting eye or another rated lifting point. The CPA guidance says the bucket should be removed where possible, and if anything stays on, its full weight is part of the load.
Why is the capacity lower over the side?
A tracked excavator is more stable along its tracks than across them, so most charts give lower figures over the side. If the load will slew round, use the over-side figure. Blades, stabilisers, counterweight and the arm fitted all change the chart too, so use the one for the machine as it is set up.
What safety devices does an excavator need for lifting?
A rated capacity table in the cab, a load hooking device or rated lifting point, and, where the rated capacity is over 1 tonne or the overturning moment over 40,000 Nm, a boom lowering control device (hose burst valves) and an overload warning device. The warning only warns: it can be muted and does not stop the lift.
Sources: ISO 10567, Earth-moving machinery — Hydraulic excavators — Lift capacity; CPA CIG 0801, Guidance on Lifting Operations in Construction When Using Excavators, Rev 2, March 2009; Strategic Forum Plant Safety Group, Lifting Operations with 180° and 360° Excavators, 2018.
Need the lift planned properly?
RMT excavator lift plans check the duty on the maker's chart for the machine as configured, and come with an elevation, an exclusion zone plan and a rigging drawing, written by a CPCS A61 Appointed Person.